Thread-cutting brace



(No Model.)

B. L. BARTON. THREAD CUTTING BRAGE.

IN VENTirj WW! 8) ATTORNEYS.

WITNESSES M'W aekz EDWARD L. BARTON, OF MILLERSBURG, ASSIGNOR OF ONE-HALF TO 0. BUTTER, JR., OF BLOOMSBURG, PENNSYLVANIA.

NITFDWT STATES PATENT ()FFICE.

JOHN

TH READ-CUTTING BRACE.

SPECIFICATION forming part of Letters Patent No. 533,407, dated January, 29, 1 895. Application filed September 21, 1894. serial No. 523,716- (No model.)

To aZZ whom it may concern.-

Be it known that I, EDWARD L. BARTON, of Millersburg, in the county of Dauphin and State of Pennsylvania, have invented a new and Improved Thread-.OuttingBrace, of which the following is a full, clear, and exact description.

My invention relates to a thread cutting brace, and it has for its object to provide a brace in which any form of die adapted 'for thread cutting may be held, and whereby the brace, with the die connected, may be manipulated in like manner as the ordinary brace.

A further object of the invention is to so construct the brace that its crank arm may be removed in a convenient and expeditious manner, and whereby also the part with which the crank arm is connected may be adjusted to form a straight handle, and thus enable the tool to be used to the greatest possible advantage.

Another feature of the invention consists in providing the brace with a simple, economic and durable form of chuck, capable of receiving and holding firmly in position a die of any desired character.

The invention consists in the novel construction and combination of the several parts, as will be hereinafter fully set forth,

and pointed out in the claims.

Reference is to be had to the accompanying drawings, forminga part of this specification, in which similar figures and letters ofreference indicate corresponding parts in all the.

views.

Figure 1 is a perspective view of the complete brace, illustrating a die held in position a in the chuck. Fig. 2 is a plan view of the brace, with the crank arm removed, illustrating the application of the straight handle to the chuck; and Fig. 3 is a vertical longitudinal section, taken practically on the line 33 of Fig. 2.

The upper portion of the brace consists of a crank arm A of the usual construction, having loosely mounted upon its upper end a breast block 10, and upon the lower member of the crank arm the usual hand block 11 is loosely mounted. The lower portion of the crank arm is squared, and above the squared brace a straight handle B, is employed. The

said straight handle comprises two bars 14 and 15, one of them being held to slide upon the other. Each bar at its outer end is provided with a handle extension, designated 'respectively as 14 and 15 and one of the bars, the bar 14 for example, near its outer end, is provided with an offset 16, upon its lower face, 6 5 while the other bar 15, is provided with a similar oifset 17, upon its upper face. These offsets are adapted to limit the inward movement of the bars one upon the other, since the inner end of the upper bar will strike the upper projection 17 of the lower bar, and the inner end of the lower bar will contact with the projection of the upper bar. Each bar is provided with a longitudinal slot, theslot in the upper bar being designated as 18 and that 7 5 in the lower bar as 19. The inner end of each bar is provided with a T-stud 20, or its equivalent, which extends through the slot of the opposite bar, and has guided movement upon said bar, the studs serving to hold the two bars in parallel relation.

In one of the bars, usually the upper bar 14 at the ofiset 16, a rectangular or polygonal opening 21, is made, and this opening is adapted to receive the squared or polygonally shaped section of the crank arm; and when this section of the crank arm is within the opening the shoulder 12 of the crank arm will rest upon the upper face of the upper handle bar, while its threaded extremity 13, 0 will extend below the said upper handle bar,

and is made to receive a nut 22, preferably block 23,which is preferably circular in cross section, and is somewhat enlarged in diameter at its upper end; and the enlarged section of the block is provided with an exterior thread 24, of any desired length. The block is provided at the top with a post or extension 25, which next to the block is squared .or rendered polygonal in cross section, while its upper or outer end is threaded, as illustrated at 26, being adapted to receive a lock nut 27, of like character as the nut 22.

In diametrically opposite sides of the body block 23 of the chuck longitudinal slots 28, are made, extending from the lower portion of the threaded surface 24 to and through the lower end of the block; and each groove or channel 28, is provided with a branch 29, which branch is curved outwardly and finds an exit through the threaded portion of the block, as is clearly shown in Fig. 3. The grooves or channels 28, are adapted to receive the upper portions of the shanks 30 of jaws 31. The jaws are two in number, and are located one opposite the other, and each jaw has formed integral with it a shank. The upper ends of the shanks, or those portions which enter the grooves or channels 28 in the body block 23, are preferably straight with the exception of their upper ends,which are reduced and. curved in an outward direction, so that when the curved portions of the shanks are entered in the curved branches 29 of the grooves or channels 28, as shown in Fig. 3, the jaws will have been pivotally connected with the body block of the chuck.

The straight portions of the shanks terminate at the lower end of the body block, and from that point the shanks are outwardly and downwardly curved. The shanks are normally forced apart through the medium of a spring 32, which spring is located in a chamber 33, formed preferably in the lower portion of the body block; and the ends of the spring are made to enter recesses in the shanks 30 of the chuck jaws, or the spring may be attached to the jaws in any other approved manner.

The jaws 31 maybe given any desired shape. In the drawings the jaws are shown as semicircular, and each jaw is provided with a rabbet 34 upon its inner face, and one of the jaws at its rabbetted face, is fitted with a feather 35, as shown best in Fig. 1; but a feather may be formed upon each jaw if in practice it is found desirable.

When the rabbet 34, is formed in the inner face of each jaw, an upper shoulder 34*, is produced; and when the jaws are made semicircular, they are adapted to receive a thread cutting die 0 of circular shape, as shown in Figs. 3 and 1, the die being provided with a marginal recess 36, to receive the feather of the jaw; but as heretofore stated the jaws may be shaped to correspond to the shape of whatever form of die they are to receive.

The shanks 30 of the jaws have sufficient movement to and from one another to accommodate large or small dies or dies of intermediate size, and the jaws are opened through the medium of the spring 32, but they are closed through the medium of a sleeve 37. This sleeve is provided at its upper end with an interior thread, and is screwed upon the threaded surface 24 of the body of the chuck. The sleeve extends downward, therefore, around the shanks of the jaws, and likewise around the body 23 of the chuck; and when the sleeve is in its upper position the lower end of the sleeve will be just above the curved section of the shanks, and the spring 32 will at that time force the jaws outward to their outer limit. After the die has been placed between the jaws, by screwing the sleeve downward the lower end of the sleeve will engage with the curved surfaces of the jaws and draw the jaws inward in direction of each other, and' therefore to a firm and clamping engagement against whatever is placed between them.

7 The chuck is fitted to the straight handle B in the following manner: The squared portion of the cap post 25 of the chuck is passed upward through the slot 19 in the lower handle bar 15, and is also passed upward through an opening 38 made in the inner end of the upper handle bar, as shown in Fig. 3. Thus the upper handle bar remains stationary while the lower bar is free to be moved inward or outward, andthe chuck is firmly held in engagement with the handle by screwing the nut 27 carried by the post 25, downward to a firm engagement with the upper handle bar.

When the tool is to be used as a regular brace, that is, when the crank arm A is attached to the straight handle B, the handle bar 19 is carried inward until the handle is shortened as much as possible, as shown in Fig. 1, and at that time the chuck is readily fastened to the straight handle section, as shown in Fig. 1; but when the crank arm cannot be used to advantage it is removed, as shown in Fig. 3, and the handle bar 19 is drawn outward as far as possible, and by this means a straight handle is formed for the chuck, the chuck being located at the center thereof.

By the use of a tool constructed as above described threads may be cut in places heretofore inaccessible, or reached with great difficulty, and the tool is also simple, durable and economic in its construction.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. A screw-cutting brace, the same consistin g of a chuck, an adjustable handle connected with the chuck, and a crank arm remo'vably attached to the handle, as specified.

, 2. A screw-cutting brac'e, the same consisting of a chuck, a handle located at right angles to the chuck and adj ustably connected substantially as shown and described.

4:. A screw-cutting brace, the same consist-Y ing of a chuck, a straight handle adjustably connected with the chuck and located at right angles thereto, the handle comprising bars held to slide one upon the other, and a locking device engaging with the bars, one of the bars being fitted to receive the crank, as and for the purpose specified.

5. In a screw cutting brace, the combination, with a crank arm, and a handle removably connected with the crank arm, said handle being constructed in members held to slide one upon the other, of a chuck comprising a body a member of which extends through the members of the handle, the body of the chuck being at right angles to the said handle, and a locking mechanism adjustably connecting the body with the handle, jaws provided with shanks, the shanks of the jaws being spring-controlled and pivoted in the body of the chuck, the jaws being adapted to hold between them a die, and a lockin g sleeve carried by the body and having clamping engagement with the shanks of the chuck jaws, substantially as shown and described.

6. ,A screw-cutting brace consisting of a chuck and a straight handle connected at right angles thereto, said handle comprising two members having sliding movement upon one another, substantially as set forth.

7. A screw-cutting brace consisting of a chuck, a handle connected at right angles thereto and comprising two members mounted to slide one upon the other, and means for locking said members in position, substan- I tially as set forth.

EDWARD L. BARTON.

Witnesses:

I. KOPPENHAUER, J. B. SEAL. 

